Matrix trimmer



March 2, 1937. J. w. FITZSIMMONS MATRIX TRIMMER Filed Jan. 20, 1936 E IQ //V1 E/V70 8. JAMES IV. FITZSIMMONE.

H/5 HTTOP/YEK Patented Mar. 2, 1937 UNITED await This??? Fi i MATRIX TRIMMER 8 Claims.

My invention relates to improvements in matrix trimmers wherein a holder is provided with a cylindrical concavity identical with the concavity of a mold for casting stereotype plates and operates in conjunction with means for holding a matrix to be trimmed in complete conformity with said concavity, and also with means for trimming superfluous material from said matrix while so held, whereby said matrix may be accurately fitted into a casting mold.

The primary object of the present invention is to provide a new and improved device for trimming matrices to exact dimensions so that they may be accurately fitted into a casting mold for casting stereotype plates.

Another object is to provide a new and improved matrix trimmer which may be easily and economically constructed and operated and having a maximum efficiency.

A further object is to provide a new and improved matrix trimmer having improved means for bending a fiat matrix to be trimmed into the exact conformation required for a casting mold and for trimming while so bent to correct size the said matrix to facilitate insertion of said matrix into said mold to facilitate the casting operation.

A still further object is to provide a new and improved device of the character described having improved means for readily moving the pressure means into and out of engaging relation or position.

I accomplish these and other objects by means of the improved device disclosed in the drawing 35 forming a part of the present application; and

in which Fig. l is a front elevation of my improved matrix trimmer;

Fig. 2 is a side elevation thereof; and

Fig. 3 is an enlarged, broken detail view, partly in section, more fully disclosing the construction and operation of the device.

Referring to the drawing:

The numeral 1 is used to designate a suitable 45 table mounted upon a support 2 provided with suitable castors 3 by means of which the device may be easily transported from one location to another.

The table I is provided upon one side with a 50 cutting edge or blade 4. A matrix holder 6, formed of a semicircular or semicylindrical plate, having a concavity 1 identical with the concavity of a casting mold for stereotype plates, not shown, as it forms no part of the present invention, is

55 mounted upon said table I, said holder 6 being positioned horizontally with its longitudinal edges arranged one above the other, the lower edge coinciding with the cutting edge or blade t while the upper edge, parallel thereto, is provided with a preferably beveled and inwardly extending limiting stop 8, the purpose of which will hereinafter be more fully set forth.

The holder 5 is rigidly held in position by means of a suitable brace 9 extending upwardly from the table I and secured to the back and approximate center of said holder, as disclosed in Fig. 2 of the drawing.

A plurality of vertically disposed spring fingers H are suitably secured to the support 2 of the table l and have their upper ends arranged in spaced relation to the cutting edge or blade 4 on the lower edge of the concavity i, said fingers ll having their upper ends provided with inwardly turned extensions if, as disclosed in Figs. 2 and 3 of the drawing.

A rod M is rotatably mounted upon the support 2 and parallel with and slightly below the cutting edge l and is provided with a plurality of flat surfaced recesses it, within which recesses it are positioned the fiat springs ll. One end of the rod I4 is bent transversely as at ii to pro vide a handle or crank by means of which the said rod may be partly rotated to cause the uncut portions of the periphery of said rod to engage and recede the spring fingers H, for a purpose hereinafter more fully set forth.

A suitable shear or cutting blade 58 is pivotally mounted, as at i9, upon the upper end of an extension ii of the support 2, to move between the upper ends of the fingers H and the cutting edge i of the table l and concavity 1 thereon and in engaging or shearing relation with said cutting edge l, said blade it being normally and resiliently held in such shearing relaticn by means of a suitable spring 22 coiled about its pivotal point 59, as disclosed in Fig. 2 of the drawing.

In operation:

By means of the extension ii the rod M is partly rotated until the uncut portions of the periphery of said rod engages and recedes the upper ends of the spring fingers ii. That is to say, that the upper ends of the spring fingers ll are moved away from the cutting edge A,

A fiat matrix 23 to be trimmed is then bent into the concavity 'i of the holder 6 with the upper edge of said matrix 23 in engaging relation with the stop 8 at the top edge of the concavity l and also moved longitudinally until said matrix engages suitable stops 2% arranged at one end of said holder 6. The lower edge of the matrix 23 is pressed below the lateral extensions l2 of the fingers H and by means of the extension ll of the rod 34 said rod is now partly rotated until the spring fingers rest within their respective fiat surfaced recesses it, which will permit the upper ends of said fingers H to engage and press upon the lower edge of the matrix 23 and press the same into close conformity with the concavity 'i of the holder 6 and the upper edge of said matrix into close contact with the beveled stop 8 so that the matrix 23 will then be in the proper shape.

The knife I8 is now moved in the direction indicated by the curved arrow in Fig. 1 of the drawing until the cutting edge thereof, in shearing relation with the cutting edge 4, trims the said matrix to the exact size of the concavity .7 thereby enabling said matrix to fit accurately into the mold for casting a stereotype plate.

As the pressure of the fingers ll upon the matrix 23 is constant it is obvious that said matrix will be effectively held in conformity with the concavity 1 of the holder 6 during the entire trimming operation so that said matrix will be trimmed to the exact size, on at least three sides thereof and circumferentially to accurately fit into the casting mold, not shown.

After the matrix 23 has been trimmed the knife or shear I8 is raised and disengaged from the cutting edge 4 and raised to a perpendicular position, as disclosed in Fig. l of the drawing, when the matrix may be readily removed from the concavity l, the shearing operation having disengaged the said matrix from the fingers H.

By means of the extension ll of the rod it said rod may be rotated to recede the spring fingers H from matrix-engaging position to facilitate the insertion of the next matrix to be trimmed. c

Having described my invention, I claim- 1. A matrix trimmer comprising a holder having a cylindrical concavity identical with the cylindrical concavity of a casting mold for stereotype plates and having a shearing edge on one longitudinal edge thereof; a limiting stop mounted upon the opposite longitudinal edge of said holder; pressure means mounted in spaced relation with the shearing edge of said concavity for bending a matrix to be trimmed against said stop and in conformation with said concavity; and shearing means mounted for movement between said pressure means and shearing edge and operating in conjunction with said shearing edge for trimming a matrix bent into said concavity to the edge thereof whereby said matrix may be accurately fitted, circumferentially, within a casting mold.

2. A matrix trimmer comprising a holder hav ing a semicylindrical concavity shaped identically with the semicylindrical concavity of a mold operating in conjunction with a matrix for casting a stereotype plate, said holder having a shearing edge on one longitudinal edge thereof; a beveled limiting stop mounted upon the opposite longitudinal edge of said holder and concavity therein; end stops for preventing longitudinal movement in one direction of a matrix bent into said concavity; a plurality of resilient pressure fingers arranged in spaced relation to said shearing edge of the concavity for pressing a bent matrix therein against the beveled stop and in close conformation with the concavity in said holder; and shearing means mounted for movement between said fingers and shearing edge and in shearing relation with said shearing edge to trim a matrix bent within said conpreventing longitudinal movement of a matrix bent into said concavity in one direction; a plurality of resilient pressure fingers arranged in spaced relation to said shearing edge of the concavity for pressing a matrix bent into said holder against the beveled stop and in close conformation with the concavity of said holder; and shearing means mounted for movement between said fingers and shearing edge and in shearing relation with said shearing edge to trim a matrix bent into said concavity to the edge thereof and in conformity with said. concavity whereby said matrix may be accurately fitted within a mold for casting a stereotype plate from said matrix; and means for moving said pressure fingers from engaging position with said matrix.

4. A matrix trimmer comprising a holder having a semicylindrical concavity shaped identically with the semicylindrical concavity of a mold operating in conjunction with a matrix for casting a stereotype plate, said holder having a shearing edge upon one longitudinal edge thereof; a beveled limiting stop mounted upon the opposite longitudinal edge of said holder and cavity therein; end stops for preventing longitudinal movement in one direction of a matrix bent into said concavity; a plurality of resilient pressure fingers arranged in spaced relation to said shearing edge of the concavity for pressing a matrix bent therein against the beveled stop and in close conformation with the concavity in said holder; shearing means mounted for movement between said fingers and said shearing edge and in shearing relation with said edge to trim a matrix bent within said concavity to the shearing edge thereof whereby said matrix may be accurately fitted within a casting mold to cast a stereotype plate from said matrix; and means for normally holding said shearing means in shearing relation with said shearing edge.

5. A matrix trimmer comprising a holder having a semicylindrical concavity shaped identically with the semicylindrical concavity of a mold operating in conjunction with a matrix for casting a stereotype plate, said holder having a shearing edge upon one longitudinal edge thereof; a beveled limiting stop mounted upon the opposite longitudinal edge of said holder and concavity thereof; end stops for preventing longitudinal movement in one direction of a matrix bent into said concavity; a plurality of resilient pressure fingers arranged in spaced relation to said shearing edge for pressing a matrix bent therein against the beveled stop and in close conformation with said concavity; shearing means mounted for movement between said fingers and said shearing edge and in shearing relation with said edge to trim a matrix bent within said concavity to the shearing edge thereof and in conformity with said concavity whereby said matrix may be accurately fitted into a casting mold for casting a plate from said matrix; and a rod rotatably mounted in connection with said holder and having cam surfaces for engaging said fingers to move the same into and out of engaging position with said matrix.

6. A matrix trimmer comprising the combination with a table of a cutting edge upon one side thereof; a holder formed of a semicircular plate mounted upon said table with one longitudinal edge matching said cutting edge and forming a concavity identical with the concavity of a casting mold operating in conjunction with a matrix for casting a stereotype plate; an inwardly extending beveled stop mounted upon the opposite longitudinal edge of said plate and concavity formed therein and arranged parallel with the cutting edge; limiting stops arranged upon one end of said holder for limiting longitudinal movement in one direction of a matrix bent within said concavity; a plurality of spring fingers arranged in spaced relation to said cutting edge for pressing a matrix to be trimmed and bent into said concavity against the beveled stop and in close conformation with said concavity; and shearing means pivotally mounted upon said table for movement between said fingers and said cutting edge and in shearing relation with said edge to trim a matrix bent to conform with said concavity whereby said matrix may be accurately fitted within a casting mold to cast a stereotype plate therefrom.

'7. A matrix trimmer comprising the combination with a table of a cutting edge upon one side thereof; a holder formed of a semicylindrical plate mounted upon said table with one longitudinal edge matching said cutting edge and forming a concavity identical with the concavity of a casting mold operating in conjunction with a .matrix for casting a stereotype plate; an inwardly extending beveled stop mounted upon the opposite longitudinal edge of said plate and concavity formed therein and arranged parallel with the cutting edge; limiting stops arranged upon one end of said holder for limiting longitudinal movement in one direction of a matrix bent into said concavity; a plurality of vertically disposed spring fingers having their free ends arranged opposite and in spaced relation to said cutting edge for engaging one edge of a matrix bent into said concavity and pressing the opposite edge thereof against the beveled stop and said matrix in close conformity with said concavity; shearing means pivotally mounted upon said table for movement between said spring fingers and said cutting edge and in shearing relation with said edge to trim a matrix bent into said concavity and extending beyond said edge whereby said matrix may be accurately trimmed by said shearing means operating in conjunction with said cutting edge; and means for normally holding said shearing means in close shearing relation with said cutting edge whereby a matrix bent into said concavity and extending beyond said edge may be trimmed closely to said edge.

8. A matrix trimmer comprising the combination with a table of a cutting edge upon one side thereof; a holder formed of a semicylindrical plate mounted upon said table with one longitudinal edge matching said cutting edge and forming a concavity identical with the concavity of a casting mold operating in conjunction With a matrix for casting a sterotype plate; an inwardly extending beleved stop mounted upon the opposite longitudinal edge of said plate and. the concavity formed therein and arranged parallel with the cutting edge; limiting stops arranged upon one end of said holder for limiting longitudinal movement in one direction of a matrix bent into said concavity; a plurality of vertically disposed spring fingers having their free ends arranged opposite and in spaced relation to said cutting edge for engaging one edge of a matrix bent within said concavity and pressing the opposite edge thereof against the beveled stop and said matrix into close conformity with said concavity; a shearing blade pivotally mounted upon said table for movement between said spring fingers and said cutting edge and in shearing relation with said edge to trim a matrix bent into said concavity and extending beyond said edge whereby said matrix may be accurately trimmed by said shearing blade operating in conjunction with said cutting edge; means for normally holding said blade in close shearing relation with said edge whereby a matrix within said concavity and extending beyond said edge may be trimmed to said edge; and means for moving said spring fingers into and out of engaging po-' sition with the lower edge of a matrix within said concavity.

JAMES W. FITZSIMMONS. 

